/* 版心 */

.nav-banner {
    display: flex;
    flex-direction: row;
    justify-content: space-between;
    position: relative;
    width: 100%;
    margin: 0 auto;
    height: 100%;
    background-color: #3DA19F;
}

.banner {
    width: 80%;
    margin: 0 auto;
    height: 100%;
}


/* 导航模块css */

.nav {
    position: fixed;
    width: 100%;
    height: 5rem;
    box-shadow: 10px 10px 10px -4px rgba(0, 0, 0, .2);
    z-index: 999999;
    overflow: hidden;
}

.navitems {
    display: flex;
    justify-content: space-between;
}

.navitems a {
    width: 9rem;
    height: 5rem;
    perspective: 500px;
    margin: 0 3%;
}

.box {
    position: relative;
    width: 100%;
    height: 100%;
    transform-style: preserve-3d;
    transition: all .4s;
    font-size: 18px;
    text-align: center;
    line-height: 5rem;
    cursor: pointer;
}

.box:hover {
    transform: rotateX(90deg);
}

.front,
.bottom {
    position: absolute;
    left: 0;
    top: 0;
    width: 100%;
    height: 100%;
}

.front {
    color: #fff;
    font-weight: 600;
    background-color: #3DA19F;
    z-index: 1;
    transform: translateZ(2.5rem);
}

.bottom {
    color: #3DA19F;
    font-weight: 600;
    background-color: #fff;
    transform: translateY(2.5rem) rotateX(-90deg);
}

.img {
    /* float: left; */
    width: 17rem;
    height: 100%;
    background: url('../images/logo.png') no-repeat;
    /* 高度填满，宽度自适应缩放 */
    background-size: auto 96%;
    vertical-align: middle;
}

.title {
    /* float: left; */
    width: 28rem;
    color: #fff;
    font-size: 1.5rem;
    font-weight: 700;
    line-height: 5rem;
    vertical-align: middle;
}

h1,
h2,
h3,
h4,
strong {
    font-weight: 600;
    color: #273849;
}

p {
    letter-spacing: 0.05em;
    font-size: 14px;
}
